I recently bought Furbie a toy, its plastic rings that hang from the top of the cage, at the end there is a bell with two red beads hanging from it. He started sleeping underneath the toy, with the bell on his head like a little hat.
I thought maybe the bell was bothering him, so I moved it to a different area of the cage...but nope...he started sleeping on the other perch, with the bell on his head. He also gets mad, screeches, and bites the bell when it moves. Its the cutest thing ever, I'll have to take a picture of him with his bell-hat